Note: Descriptions are shown in the official language in which they were submitted.
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
A MILD CATALYTIC REDUCTION OF C-0 BONDS AND C=0 BONDS
USING A RECYCLABLE CATALYST SYSTEM
FIELD OF INVENTION
The present invention relates to eco-friendly methodology for the conversion
of alcohols to hydrocarbons as
well as conversion of carbonyls such as aldehydes and ketones to alcohols and
then hydrocarbons
BACKGROUND
Alcohols are versatile organic compounds reagents and can be used as
precursors for other classes of or-
ganic molecules in synthetic chemistry. Catalytic hydrogenolysis of C¨OH bonds
is a very important synthetic
technique; it is widely used in organic synthesis [1-3], pharmaceutical
production [4,5] and biomass conver-
sion [6-8]. Reduction of alcohols to the corresponding hydrocarbon is usually
accomplished sequence of
steps. Conventionally, hydrogenolysis of C¨OH bond is achieved with molecular
hydrogen using noble met-
als as catalysts. In some cases, stoichiometric reducing agents such as metal
hydrides are used. Neverthe-
less, these traditional hydrogenolysis methods have some drawbacks. One
drawback is the use of molecular
hydrogen or stoichiometric reducing agents that often causes safety and
environmental problems, because
molecular hydrogen and metal hydrides are flammable, explosive and hazardous.
Another drawback is the
use of high temperature and high-pressure that will necessitate expensive high-
pressure equipment, thereby
increasing the cost of the process and resulting in many troubles in
manipulation. An additional drawback is
its low selectivity due to the hash reaction conditions employed. In contrast
to the traditional hydrogenolysis
methods, catalytic transfer hydrogenolysis (CTH) uses hydrogen donors to
provide hydrogen species in situ;
hence it offers the possibility to overcome the drawbacks of the traditional
hydrogenolysis methods.
CTH is an important synthetic technique in organic chemistry. As neither
hydrogen containment nor a pres-
sure vessel is required; the mild reaction conditions offer considerable
advantages over the conventional
method of catalytic hydrogenolysis. For the transfer hydrogenolysis or
hydrogenation, it is necessary to se-
lect an efficient catalyst and suitable hydrogen donors. Recently, formic acid
has been employed as the
source of hydrogen and has many advantages in regards to handling, transport,
and storage and can easily
be generated form hydrogen gas and carbon dioxide.
Generally, metal (VIII group elements) such as palladium ruthenium and Raney
nickel are employed as the
catalysts for the transfer hydrogenolysis. Palladium is arguably one of the
most powerful and versatile transi-
tion-metal catalysts which can be immobilized on various heterogeneous
supports and be used for a variety
1
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
of organic transformations. Palladium heterogeneous catalyst can be recycled
by simple filtration and reused
in several cycles without the loss of efficiency with the consequently
advantages such as economic and
environmental. Recently, we developed asymmetric carbocyclizations
implementing a heterogeneous palla-
dium catalyst with a simple chiral amine co-catalyst. However, it is not sure
whether the Palladium heteroge-
neous catalyst could be reused for the 0TH of alcohols.
OBJECT OF THE INVENTION
It is an objective of the invention to hydrocarbons from alcohols using a
heterogeneous metal catalyst sys-
tem.
Another objective of the invention is to synthesize hydrocarbons from
aldehydes or ketones using a hetero-
geneous metal catalyst system.
Another objective of the invention is to depolymerize lignin followed by the
above conversion of carbonyls or
alcohols to hydrocarbons, respectively.
Another objective of the invention is to link it to selective catalytic
oxidations of arylpolydiols such as lignin
followed depolymerization and then conversion of carbonyls or alcohols to
hydrocarbons, respectively.
A still further objective of the invention is to provide a method of the
aforementioned kind that is advanta-
geous from an environmental and health standpoint.
Even more objectives will become evident from a study of the summary of the
invention, a number of pre-
ferred embodiments illustrated in a drawing, and the appended claims.
SUMMARY OF THE INVENTION
The invention is based on the use of a heterogeneous metal catalyst that can
convert alcohols to hydrocar-
bons using a suitable reducing agent (Scheme 1).
2
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Heterogeneous Metal
OH Catalyst
ArR
ArR
2
1
Scheme 1
Another aspect of the invention is the use of a heterogeneous metal catalyst
that can convert an ether bond
beta to a hydroxyl group or alpha to a carbonyl group to hydrocarbons,
respectively, using suitable reducing
agents.
Another aspect of the invention is the use of a heterogeneous metal catalyst
that can convert aldehydes or
Heterogeneous Metal Heterogeneous Metal
0Catalyst OH Catalyst
ArR
ArR
ArR
suitable suitable
2
reducing 1 reducing
agent agent
ketones to hydrocarbons, respectively, using suitable reducing agents (Scheme
2).
Scheme 2
Another, aspect of the invention is the catalytic selective oxidation of
primary or secondary alcohols of "lignin-
type" structure to the corresponding carbonyl, respectively. Followed by one-
pot depolymerization and then
reduction by a heterogeneous metal catalyst to the corresponding hydrocarbon
using a suitable reducing
agent (Scheme 3).
0,
HO
0
0 catalyst 2.. 101
0:me Depolymenzation
10 oxidat OMe ________ OMe
+ HO
OMe lon is
OMe
HO Catalyst 1
lower molecular weight and Higher C/O ratio
H '0-Arl Green selective oxidation H0
Ar
Depolymerization 0
2 oxidatIon 0 0 417, catalyst 3
OMe all HO
Some OMe
H0
OMe
OMe
OMe OR
Scheme 3
3
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Another, aspect of the invention is the synthesis of hydrocarbons and similar
compounds starting from lignin
and its derivatives using a combination of selective oxidations followed by
depolymerization.
The method of the invention is composed of key steps in which lignin is
converted under environmentally
benign conditions. In one embodiment of the invention the method comprises the
steps of:
i. Providing an alcohol
ii. Chemically converting the said alcohol to a carbonyl by a suitable
modification method, i.e. oxida-
tion
iii. Convert the carbonyl to another carbonyl compound using a suitable
depolymerization system
iv. Conversion of the carbonyl to the corresponding alcohol by using a
suitable heterogeneous metal
catalyst and reducing agent
v. Conversion of the said alcohol to the corresponding hydrocarbon by
using a suitable heterogeneous
metal catalyst and reducing agent.
The oxidations can be performed in water or organic solvents. Suitable
catalysts, depending on the nature of
the reactive molecule, may be a heterogeneous metal catalyst, homogeneous
metal catalyst, a metal-free
catalyst, or an enzyme. Suitable oxidants, depending on the nature of the
reactive molecule, may be oxygen,
air, hydrogen peroxide.
The oxidized oligomer or polymer with a lignin-type structure is directly
depolymerized to a smaller size car-
bonyl compound by using basic, oxidative, radical or organocatalytic
conditions.
The carbonyl groups from the previous step are reduced to the corresponding
alcohol by the heterogeneous
catalyst using a suitable reducing agent. Suitable reducing agents, depending
on the nature of the reactive
molecule, may be hydrogen, formic acid, ammonium formiate.
The alcohol groups from the previous step are reduced to the corresponding
hydrocarbons by the heteroge-
neous catalyst using a suitable reducing agent. Suitable reducing agents,
depending on the nature of the
reactive molecule, may be hydrogen, formic acid, ammonium formiate.
In another embodiment of the invention the method comprises the steps of:
ii. Providing an aldehyde or ketone
4
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
iii. Convert the carbonyl to another carbonyl compound using a suitable
depolymerization system.
iv. Conversion of the carbonyl from step iii to the corresponding alcohol
by using a suitable heteroge-
neous metal catalyst and reducing agent
v. Conversion of the said alcohol to the corresponding hydrocarbon by using
a suitable heterogeneous
metal catalyst and reducing agent.
The carbonyl groups are reduced to the corresponding alcohol by the
heterogeneous catalyst using a suita-
ble reducing agent. Suitable reducing agents, depending on the nature of the
reactive molecule, may be
hydrogen, formic acid, ammonium formiate.
The alcohol groups from the previous step are reduced to the corresponding
alcohol by the heterogeneous
catalyst using a suitable reducing agent. Suitable reducing agents, depending
on the nature of the reactive
molecule, may be hydrogen, formic acid, ammonium formiate.
Hence, in view of the above, the objects of the present is attained by a
method of conversion of a C=0 bond
to a C-H bond, comprising the steps of:
i. Providing an alcohol and converting the alcohol to a compound comprising
a C=0 bond, wherein
the compound comprising a C=0 is selected from an aldehyde and a ketone,
wherein the conver-
sion of the alcohol to a compound comprising a C=0 bond comprises the step of:
a. Oxidation with an oxidant and catalyst, wherein the oxidant is selected
from H202, 02 and
Na0C1, and wherein the catalyst is selected from heterogeneous supported metal
catalyst,
homogeneous organometallic complex,a metal-free catalyst (mediator), and
enzyme (EC
1:10:3:2), and
ii. Providing the compound comprising a C=0 bond from the previous step,
and
iii. Reducing said compound comprising a C=0 bond in a solvent comprising
reducing agent and a
catalyst, wherein the catalyst is selected from a heterogeneous metal catalyst
and homogeneous
organometallic complex, wherein the heterogeneous metal catalyst is a Pd(0)-
nanocatalyst which is
heterogeneously supported on silica containing material, wherein the
homogeneous organometallic
complex comprises Pd, Ir, Ru, Ni, Co, Cu complexes.
In a preferred embodiment of the present invention, the catalyst is a Pd-
catalyst selected from Pd(0)-amino
functionalized silica support, preferably Pd(0)-AmP-silica support.
5
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
In a further preferred embodiment, the catalyst is a Pd-catalyst selected from
Pd(0)-AmP-MCF and Pd(0)-
AmP-CPG, preferably the Pd-catalyst is recyclable.
In a further preferred embodiment, the reducing agents are ammonium formiate
and H2 gas, and wherein the
solvent is preferably toluene. Moreover, the reduction may be carried out at a
temperature of 20-80 C, pref-
erably at ambient temperature or 80 C.
In a further preferred embodiment, the alcohol is converted to an aldehyde in
step i), wherein the conversion
of the alcohol to an aldehyde is conducted in the presence of Na0C1, TEMPO
(2,2,6,6-Tetramethylpiperidin-
1-yl)oxyl), NaOH, KBr and 02, and wherein step i) may comprise the steps of:
a. Adding a solution of KBr to a solution comprising the alcohol and TEMPO,
preferably KBR is
in a water solution and TEMPO is in CH2C12,
b. Stirring the mixture, preferably at 0 C,
c. Na0C1 solution is added to the reaction mixture, preferably the Na0C1
solution has pH 9,
d. Adding NaOH to the reaction mixture in the presence of 02, and
e. Stirring the mixture, preferably at 0 C, more preferably at 0 for 3
hours.
In a further preferred embodiment, the alcohol is converted to a ketone in
step i), wherein the conversion of
the alcohol to a ketone is conducted in the presence of 02, TEMPO, HNO3 and
HCI, and wherein step i) may
comprise the steps of:
a. Adding TEMPO to the alcohol in the presence of 02,
b. Adding a mixture of HNO3 in acetonitrile,
c. Adding a mixture of HCI in acetonitrile, preferably also adding water and
acetonitrile, and
d. Optionally heating the mixture.
In a further preferred embodiment, the alcohol is a diol, and wherein said
diol is in step i) converted to an
aldol which then undergoes a spontaneous catalytic retro-aldol reaction to the
corresponding aldehyde moie-
ties, and wherein the 0=0 bond of the aldehydes are subsequently reduced to a
C-H bond in step iii).
In a further preferred embodiment, the diol is selected from lignin and
derivatives thereof, preferably the
alcohol is lignin containing benzylic, allylic or aliphatic alcohols including
13-0-4 aryl ether linkages, more
6
CA 02965879 2017-04-26
WO 2016/066835
PCT/EP2015/075333
preferably the lignin is selected from milled wood lignin, cellulolytic
lignin, organosolv lignin and technical
lignin from pulping processes, wherein the method may comprise the steps of:
i. Providing lignin and oxidizing the lignin to a polymer comprising
aldehyde groups,
ii. The polymer comprising aldehyde groups which have been provided in the
previous step
subsequently undergo spontaneous catalytic retro-aldol reaction which leads to
a depoly-
merization,
iii. Reducing the aldehyde groups.
In a further preferred embodiment, the alcohol is a primary alcohol, and
wherein the primary alcohol is con-
verted to an aldehyde in step i), and wherein the 0=0 bond of the aldehyde is
subsequently reduced to a 0-
H bond.
In a further preferred embodiment, the alcohol is selected from vanillyl
alcohol, hydroxy-, methoxy- and eth-
oxybenzyl alcohols, and wherein vanillyl alcohol, hydroxy-, methoxy- and
ethoxybenzyl alcohols are convert-
ed to their respective aldehydes in step i), and wherein the 0=0 bond of the
aldehyde is subsequently re-
duced to a C-H bond.
In a further preferred embodiment, the alcohol is a secondary alcohol, and
wherein said secondary alcohol is
converted to a ketone in step i), and wherein the 0=0 bond of the ketone is
subsequently reduced to a C-H
bond.
In a further preferred embodiment, the object of the invention is attained by
the products obtainable by the
above preferred embodiments. Furthermore, the object of the invention is also
attained by using said prod-
ucts as fuels.
The objects of the present is also attained by a method of conversion of a 0-0
or 0=0 bond to a C-H bond,
comprising the steps of:
i. Providing a compound comprising a 0-0 bond or a 0=0 bond, wherein said
compound is selected
from an aldehyde, a ketone, an alcohol, an aldol, a compound having an ether
bond beta to a hy-
droxyl group, or a compound having an ether bond alpha to a carbonyl group,
and
ii. Reducing the 0-0 or 0=0 bond to a C-H bond in a solvent comprising
reducing agent and a cata-
lyst, wherein the catalyst is selected from heterogeneous metal catalyst and
homogeneous organ-
ometallic complexõ wherein the heterogeneous metal catalyst is a Pd(0)-
nanocatalyst which is het-
7
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
erogeneously supported on silica containing material, wherein the homogeneous
organometallic
complex comprises Pd, Ir, Ru, Ni, Co, Cu complexes and
wherein an optional step of providing an alcohol and then converting the
alcohol to a compound
comprising a C=0 bond is provided before step i).
In a further embodiment, the catalyst is a Pd-catalyst selected from Pd(0)-
amino functionalized silica support,
preferably Pd(0)-AmP-silica support.
In a further preferred embodiment, the catalyst is a Pd-catalyst selected from
Pd(0)-AmP-MCF and Pd(0)-
AmP-CPG, preferably the Pd-catalyst is recyclable.
In a further preferred embodiment, the reducing agent is selected from
hydrogen, formic acid and ammonium
formiate.
In a further preferred embodiment, the reducing agent is ammonium formiate and
formic acid when the com-
pound comprising a C-0 bond is an alcohol, and wherein the solvent may be
ethanol and/or water, prefera-
bly a mixture of ethanol and water, more preferably the mixture of ethanol and
water having a ratio of etha-
nol:water being 4:1. Moreover, ammonium formiate and formic acid may be added
- in a ratio of 0.25 and 6.6, respectively, in relation to the alcohol, or
¨ in a ratio of 0.25 and 3.3, respectively, in relation to the alcohol.
In a further preferred embodiment, the reducing agents are ammonium formiate
and H2 gas when the com-
pound comprising a C=0 bond is an aldehyde, ketone, an aldol, a compound
having an ether bond beta to a
hydroxyl group, or a compound having an ether bond alpha to a carbonyl group,
and wherein the solvent is
preferably toluene.
In a further preferred embodiment, the reduction is carried out at a
temperature of 20-80 C, preferably at
ambient temperature or 80 C, most preferably at ambient temperature.
In a further preferred embodiment, a step of providing an alcohol and then
converting the alcohol to a com-
pound comprising a C=0 bond is provided before step i), wherein said alcohol
is preferably selected from a
diol, primary alcohol and secondary alcohol, most preferably said alcohol is
lignin.
In a further preferred embodiment, the object of the invention is attained by
the products obtainable by the
above preferred embodiments. Furthermore, the object of the invention is also
attained by using said prod-
ucts as fuels.
8
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
DETAILED DESCRIPTION
The present invention relates to a method of conversion of a 0-0 or 0=0 bond
to a C-H bond. The method,
comprises the steps of (i) providing a compound comprising a 0-0 bond or a 0=0
bond, and then (ii) reduc-
ing the 0-0 or 0=0 bond to a C-H bond. A compound comprising a 0=0 bond is for
example an aldehyde
molecule and the 0=0 bond is in the method according to the present invention
reduced to a C-H bond, i.e.
the aldehyde is reduced to its corresponding hydrocarbon.
The method of conversion of a 0-0 or 0=0 bond to a C-H bond can also be used
in a method of converting
lignin to fuels. However, the lignin must first undergo oxidization and
depolymerization to compounds having
aldehyde groups. The resulting 0=0 moieties of the aldehyde groups are
thereafter reduced C-H moieties.
The final product may be used as fuels.
It is important to note that the oxidization reaction is not limited only to
lignin. Other alcohols, including prima-
ry alcohols, secondary alcohols and diols can all be subjected to the
oxidization reaction which yields an
aldehyde. Moreover, diols such as lignin can also be oxidized to ketones.
The oxidization reaction, i.e. conversion of an alcohol to a compound
comprising a 0=0 bond (i.e. aldehyde
or ketone), involves oxidation with an oxidant and catalyst. The oxidant may
be selected from H202, 02 and
Na0C1, while the catalyst is selected from heterogeneous supported metal
catalyst, homogeneous organo-
metallic complex and a metal-free catalyst (mediator) and enzyme (EC
1:10:3:2). In the next step the com-
pound comprising a 0=0 is reduced with a reducing agent and heterogeneous
metal catalyst.
As already indicated, the alcohol (such as lignin) can be oxidized to an
aldehyde or ketone. The conversion
of the alcohol to an aldehyde is conducted in the presence of Na0C1, TEMPO
(2,2,6,6-Tetramethylpiperidin-
1-yl)oxyl), NaOH, KBr and 02 (see Examples 9-12). First, a solution of KBr is
added to a solution comprising
the alcohol and TEMPO. The mixture is then stirred and a basic Na0C1 solution
is added to the reaction
mixture followed by adding NaOH to the reaction mixture in the presence of 02.
The alcohol is converted to a ketone in the presence of 02, TEMPO, HNO3 and
HCI (see Example 8). The
conversion involves adding TEMPO to the alcohol in the presence of 02. In the
next step HNO3 and HCI are
added to the mixture followed by heating.
When the alcohol is a diol, the diol is oxidized with oxidant and catalyst to
an aldol which then undergoes a
spontaneous catalytic retro-aldol reaction to the corresponding aldehyde
moieties (see Examples 6 and 7).
The 0=0 bonds of the aldehydes are subsequently reduced to a C-H bonds by the
reducing agent and het-
erogeneous metal catalyst.
9
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
A preferred diol is lignin and derivatives thereof. The lignin may be selected
from milled wood lignin, cellulo-
sic lignin, organosolv lignin and technical lignin from pulping processes. The
lignin is oxidized with oxidant
and catalyst to a polymer comprising aldehyde groups which undergo spontaneous
catalytic retro-aldol reac-
tion which leads to a depolymerization (Example 13). In the subsequent step
the aldehyde groups are re-
duced with reducing agent and heterogeneous metal catalyst. Moreover, the
alcohol may be a primary alco-
hol which is first converted to an aldehyde and then the 0=0 group is reduced
to a C-H bond. Primary alco-
hols may be selected from vanillyl alcohol, hydroxy-, methoxy- and
ethoxybenzyl alcohols, and wherein vanil-
lyl alcohol, hydroxy-, methoxy- and ethoxybenzyl alcohols.
A further alternative is to use a secondary alcohol which is first oxidized to
a ketone wherein the 0=0 bond of
the ketone is subsequently reduced to a C-H bond.
For the reduction step, the heterogeneous metal catalyst is a Pd(0)-
nanocatalyst which is heterogeneously
supported on silica containing material. The Pd-catalyst may selected from
Pd(0)-amino functionalized silica
support such as Pd(0)-AmP-silica support. Specific examples of Pd(0)-
nanocatalyst are Pd(0)-AmP-MCF
and Pd(0)-AmP-CPG (see Example 1). The Pd-catalyst is preferably recyclable
(see Example 3 for recycling
process). Alternatively, the catalyst may be a homogeneous organometallic
complex which may have a
complex comprising Pd, Ir, Ru, Ni, Co, Cu complexes (see Example 13).
The reducing agents for reducing the aldehyde or a ketone are ammonium
formiate and H2 gas. The reduc-
tion can be carried in various temperatures such as at 20-80 C. Although the
reduction can be carried out at
80 C, ambient temperature (i.e. room temperature of about 22 C) is more
convenient than and as effective
as higher temperatures (see Example 1).
Importantly, the products obtained by the above described methods
(particularly the method involving lignin)
can be used as fuels.
It should be noted that the method of converting a 0-0 or 0=0 bond to a C-H
bond does not necessarily
have to involve an oxidation reaction. Instead of having an alcohol such as
lignin as a starting compound, the
starting compound may be a compound having a 0-0 or 0=0 bond such as an
aldehyde, a ketone, an alco-
hol, an aldol, a compound having an ether bond beta to a hydroxyl group, or a
compound having an ether
bond alpha to a carbonyl group. The 0-0 or 0=0 bond is reduced to a C-H bond
by a reducing agent and
heterogeneous metal catalyst (see Examples 1, 2, 4 and 5).
The heterogeneous metal catalyst is a Pd(0)-nanocatalyst which is
heterogeneously supported on silica
containing material, preferably recyclable. Specific examples of these types
of catalyst have already been
mentioned above (see also Example 1) and the reducing agent is selected from
hydrogen, formic acid and
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
ammonium formiate (See Examples 2, 4 and 5).Alternatively, the catalyst may be
a homogeneous organo-
metallic complex which may have a complex comprising Pd, Ir, Ru, Ni, Co, Cu
complexes (see Example 13).
The reducing agent is ammonium formiate and formic acid when the compound
comprising a 0-0 bond is an
alcohol (Example 2). However, the reducing agents are ammonium formiate and H2
gas when the compound
comprising a 0=0 bond is an aldehyde (Example 5), ketone, an aldol, a compound
having an ether bond
beta to a hydroxyl group, or a compound having an ether bond alpha to a
carbonyl group (Example 4).
The product obtainable by the above described reduction methods can be used as
fuels.
EXAMPLES
General methods
(IR) spectra were recorded on Thermo Fisher Nicolet 6700 FT-IR spectrometer,
nmax in cm-1. Bands are
characterized as broad (br), strong (s), medium (m), or weak (w).
1H NMR spectra were recorded on a Bruker Avance (500 MHz) spectrometer.
Chemical shifts are reported in
ppm from tetramethylsilane with the solvent resonance resulting from
incomplete deuterium incorporation as
the internal standard (CDCI3: 6 7.26 ppm). Data are reported as follows:
chemical shift, multiplicity (s = sin-
glet, d = doublet, q = quartet, br = broad, m = multiplet), and coupling
constants (Hz), integration.
130 NMR spectra were recorded on a Bruker Avance (125.8 MHz or 100 MHz)
spectrometer with complete
proton decoupling. Chemical shifts are reported in ppm from tetramethylsilane
with the solvent resonance as
the internal standard (CDCI3: 6 77.16 ppm).
High-resolution mass spectrometry was performed on Agilent 6520 Accurate-Mass
Q-TOF LC/MS (positive
mode).
Chemicals and solvents were either purchased puriss p. A. from commercial
suppliers or were purified by
standard techniques. Commercial reagents were used as purchased without any
further purification.
Aluminum sheet silica gel plates (Fluka 60 F254) were used for thin-layer
chromatography (TLC), and the
compounds were visualized by irradiation with UV light (254 nm) or by
treatment with a solution of phospho-
molybdic acid (25 g), Ce(504)2=H20 (10 g), conc. H2504 (60 mL), and H20 (940
mL), followed by heating.
Purification of the product was carried out by flash column chromatography
using silica gel (Fluka 60, particle
size 0.040-0.063 mm).
11
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Example 1 - Optimization studies (Table 1)
A microwave-vial containing a solution of 1a (0.4 mmol, 1.0 equiv.), ammonium
formiate and Pd(0)-
Nanocatalyst (palladium-aminopropyl-mesocellular foam (Pd(0)-AmP-MCF), 26.8
mg, 0.02 mmol, 8 wt%, 5
mol /0) [1] or (palladium-aminopropyl-controlled pore glass (Pd(0)-CPG), 569A,
148.0 mg, 0.02 mmol, 135
pmol/g) in Et0H (2.4 mL) and H20 (0.6 mL) was stirred for 10 minutes at room
temperature. Afterwards was
added formic acid and the resulting mixture was stirred at room temperature
for the time shown in table.
NMR samples for NMR-yield were prepared by removing 0.05 mL aliquots from the
reaction mixture, filtration
through Celite using CDCI3 (1.5 mL) as eluent and mesitylene was used as an
internal standard.
12
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Table 1
0 OH Pd catalyst (5 mol%)
].. 0
HO H000NH4, HCO2H, Et0H:H20 (4:1) HO
OMe OMe
1a 2a
Entry Pd catalyst H000NH4 (equiv.) HCO2H (equiv.) temp ( C) time (h) Conv.(%)a
1 Pd/C 0.25 3.3 80 1 50[e]
2 Pd(0)-AmP-MCF 0.25 3.3 80 0.5 78
3 Pd(0)-AmP-MCF 0.25 3.3 100 0.5 69
4 Pd(0)-AmP-MCF 0.50 3.3 80 0.5 74
5b Pd(0)-AmP-MCF 0.25 3.3 80 0.5 49
6C Pd(0)-AmP-MCF 0.25 3.3 80 0.5 53
7 Pd(0)-AmP-CPG 0.25 3.3 80 0.5 54
8 Pd(0)-AmP-MCF 0.25 80 0.5 <1
9 Pd(0)-AmP-MCF 3.0 80 0.5 45
Pd(0)-AmP-MCF 0.25 6.6 80 0.5 94
11 Pd(0)-AmP-CPG 0.25 6.6 80 0.5 51
12 Pd(0)-AmP-MCF 0.25 6.6 22 1 >99
13 Pd(0)-AmP-CPG 0.25 6.6 22 1 >99
14 Pd/C 0.25 6.6 22 1 41[e]
15d Pd(0)-AmP-MCF 3.0 22 24 8
16d Pd(0)-AmP-MCF 3.0 80 9 >99
17 Pd(0)-AmP-MCF 6.6 22 1 52
18 Pd(0)-AmP-MCF 0.25 6.0 22 1
19 Pd(0)-AmP-MCF 0.25 5.0 22 1 >90
[a] Determined by analysis of 1H-NMR of unpurified mixtures. [b] 10 MOrYo MCF-
Pd(0). [c]
2.5 mol% MCF-Pd(0). [el] The reaction was performed with toluene. [e]The same
cony after
24h.
13
CA 02965879 2017-04-26
WO 2016/066835
PCT/EP2015/075333
Example 2 - Examples of converting alcohols to hydrocarbon (Table 2)
Pd(0) (5 mol%), HCOONH4 (25 mol%)
Alcohol . product
HCO2H (6 equiv.), Et0H/H20 (4:1),
12
time (h), 22 C
Procedure: A microwave-vial containing a solution of 1 (0.4 mmol, 1.0 equiv.),
ammonium formiate (6.0 mg,
0.095 mmol, 25mo1 /0) and Pd(0)-Nanocatalyst (Pd(0)-AmP-MCF, 26.8 mg, 0.02
mmol, 8 wt%, 5 mol%) [2]
or (Pd(0)-CPG, 569A, 148.0 mg, 0.02 mmol, 135 pmol/g) in Et0H (2.4 mL) and H20
(0.6 mL) was stirred for
minutes at room temperature. Afterwards was added formic acid (0.09 mL, 2.4
mmol, 6 equiv.) and the
resulting mixture was stirred at room temperature for the time shown in table.
NMR samples for NMR-yield
were prepared by removing 0.05 mL aliquots from the reaction mixture,
filtration through Celite using CDCI3
10 (1.5 mL) as eluent and mesitylene was used as an internal standard.
Before the purification of the products,
the crude reaction mixture was filtrated through Celite using CHCI3 (10 mL) as
eluent and evaporated. The
crude material was purified by silica gel flash column chromatography.
14
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Table 2
OH Pd catalyst (5 mol%),
ArR HCO2H (6 equiv.)
ArR
H000NH4 (25 mol%)
1 2
Et0H/H20 (4:1), 2200
Entry Pd catalyst Alcohol Product time (h) Yield.(%)a
1 Pd(0)-AmP-MCF 2a 0 OH 1 95
2 Pd(0)-AmP-CPG HO HO I
1 93b
OMe OMe
0 0
4 Pd(0)-AmP-MCF OH
02N H2N 2b 1 93b
0
Pd(0)-AmP-MCF OH
1. 2c 4 96
OMe OMe
OMe OMe
6 Pd(0)-AmP-MCF 0 OH
1. 2d 1 94b
7 Pd(0)-AmP-CPG 1 91b
OH
8 Pd(0)-AmP-MCF
le 0 2e 1 96b
OH
9 Pd(0)-AmP-MCF
101. 2f 1 93
H2N H2N
OH
Pd(0)-AmP-MCF
le10 2g 8 98b
Me0 Me0
OH
11 Pd(0)-AmP-MCF 0 10 1. I. 2h 1 97
HO 0
12 Pd(0)-AmP-MCF 0 2i 1 92
OH
13 Pd(0)-AmP-MCF 3 91b
14 Pd(0)-AmP-CPG 10 10 2j
3 90b
[a] Isolated yield of pure 2 . [b] H-NMR yield using mesitylene as internal
standard.
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Characterization of products
Toluene
1401
Spectra identical to the reported [3]; 1H NMR (500 MHz, CDCI3): d 7.20-7.15
(m, 2H), 7.11-7.05 (m, 3H), 2.28
(s,3H).
p-toluidine
0
H2N
Spectra identical to the reported [4]; 1H NMR (500 MHz, CDCI3): d 6.93 (d, J =
8.7 Hz, 2H), 6.62 (d, J = 8.6
Hz, 2H), 2.18 (s,3H).
1,2-dimethoxy-3-methylbenzene
0 OMe
OMe
Colorless oil; IR (neat) n 2935 (m), 2834 (w), 1586 (m), 1484 (s), 1425 (m),
1268 (s), 1222 (s), 1174 (m),
1081 (s), 1009 (s), 805 (w), 747 (s), 686 (m); 1H NMR (500 MHz, CDCI3): d 6.95
(t, J = 8.2 Hz, 1H), 6.78-6.75
(m, 2H), 3.85 (s, 3H), 3.80 (s, 3H), 2.28 (s,3H); 13C NMR (125.8 MHz, CDCI3):
d 152.9, 147.5, 132.2, 123.8,
123.0, 110.1, 60.2, 55.8, 15.9; HRMS (ESI+) [M+H] calcd for C9H1302: 153.0916,
found: 153.0906;
2-methoxy-4-methylphenol
1401
HO
OMe
Colorless oil; IR (neat) n 3511 (b), 2923 (m), 1608 (w), 1514 (s), 1464 (m),
1364 (w), 1271 (s), 1234 (m),
1206(m), 1150(m), 1122 (w), 1034(m), 919 (w), 810(m), 590(w), 559(w) cm-1; 1H
NMR (500 MHz, CDCI3):
d 6.83 (d, J = 7.9 Hz, 1H), 6.71-6.67 (m, 2H), 5.45 (s, 1H), 3.89 (s, 3H),
2.31 (s,3H); 13C NMR (125.8 MHz,
CDCI3): d 146.2, 143.3, 129.6, 121.5, 114.1, 111.6, 55.8, 21.0; HRMS (ESI+)
[M+H] calcd for C81-11102:
139.0759, found: 139.0752;
16
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
1-ethylbenzene
1401
Spectra identical to the reported [5]; 1H NMR (500 MHz, CDCI3): d 7.28 (m,
2H). 7.18 (m, 3H), 2.65 (q, 2H, J
= 7.5 Hz), 1.24 (t, 3H, J= 7.5 Hz).
4-ethylbenzenamine
0
H2N
Brown solid; IR (neat) n 3354 (b), 2963 (m), 2929 (m), 2870 (m), 2360 (w),
1686 (s), 1612 (m), 1516 (s),
1455 (w), 1411 (m), 1310 (m), 1180 (w), 1123 (w), 827 (m), 755 (m), 474 (w) cm-
1; 1H NMR (500 MHz,
CDCI3): d 7.03 (d, J = 8.4 Hz, 2H), 6.69 (d, J = 8.4 Hz, 2H), 5.79 (s, 2H),
2.57 (m, 2H) , 1.21 (t, J = 7.6 Hz,
3H); 13C NMR (125.8 MHz, CDCI3): d 128.3, 128.3, 128.2, 120.3, 119.3, 118.0,
28.0, 15.5; HRMS (EV)
[M+H] calcd for C8H12N 122.0969, found: 122.0965.
1-ethy1-4-methoxybenzene
0
Me0
Spectra identical to the reported [6]; 1H NMR (500 MHz, CDCI3): 7.11 (d, J =
8.5 Hz, 2H), 6.83 (d, J = 8.5 Hz,
2H), 3.78 (s, 3H), 2.59 (q, J = 7.6 Hz, 2H), 1.21 (t, J= 7.6 Hz, 3H).
Diphenylmethane
Os
17
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
White solid; IR (neat) n 3060 (w), 3025 (w), 2907 (w), 2842 (w), 1598 (w),
1492 (m), 1450 (m), 1075 (w),
1028 (w), 729 (s), 715 (s), 606 (m), 551 (w), 456 (m) cm-1; 1H NMR (500 MHz,
CDCI3): d 7.34-7.27 (m,4H),
7.24-7.18 (m,6H), 4.00 (s, 2H); 13C NMR (125.8 MHz, CDCI3): d 141.3, 129.1
(40), 128.6 (40), 126.2 (30),
42.1; HRMS (ESI) [M-H] calcd for C13H11 167.0861, found: 167.0854.
Triphenylmethane
0
SO
White solid; IR (neat) n 3462 (b), 3060 (w), 1596 (w), 1489 (m), 1443 (m),
1326 (w), 1154 (m), 1068 (w),
1007 (m), 889 (m), 755 (s), 694 (s), 636 (s), 581 (m), 466 (m) cm-1; 1H NMR
(500 MHz, CDCI3): d 7.36-7.30
(m,15H), 2.82 (s, 1H); 13C NMR (125.8 MHz, CDCI3): d 146.8, 128.6- 127.23 (m),
82.0; HRMS (ESI) [M-H]
calcd for 019H15 243.1174, found: 243.1168.
1-propylbenzene
1401
Spectra identical to the reported [7]. 1H NMR (500 MHz, 0D013)[7]: 7.42-7.04
(m, 5H), 2.49 (t, 2H), 2.05-1.82
(m, 2H), 0.9 (t, 3H).
Example 3 - Procedure for the recycling of the Pd nanoparticles (Table 3)
A microwave-vial containing a solution of la (61.7 mg, 0.4 mmol, 1.0 equiv.),
ammonium formiate (6.0 mg,
0.095 mmol, 25mo1 /0) and Pd(0)-Nanocatalyst (Pd(0)-AmP-MCF, 26.8 mg, 0.02
mmol, 8 wt%, 5 mol /0) [8]
or (Pd(0)-CPG, 569A, 148.0 mg, 0.02 mmol, 135 pmol/g) in Et0H (2.4 mL) and H20
(0.6 mL) was stirred for
10 minutes at room temperature. Afterwards was added formic acid (121.6 mg,
0.1 mL, 2.64 mmol, 6.6
18
CA 02965879 2017-04-26
WO 2016/066835
PCT/EP2015/075333
equiv.) and the resulting mixture was stirred at room temperature for lh.
Next, the reaction mixture was
transferred to a centrifuge-vial and Et0H (8 mL) was added and after
centrifugation, the supernatant liquid
was removed and the catalyst washed with Et0H (8 mL) 3 times. Afterwards the
catalyst was dried under
vacuum and then washed with CH2Cl2 (8 mL) three times and then dried under
vacuum.
Table 3.
(OH MCF-Pd(0) (5 mol%), H000NH4 (25 mol%)õ,
001
HCO2H (6.6 equiv.), Et0H:H20 (4:1), r.t.
HO HO
OMe OMe
la 2a
Cycle Time (h) Conv.(%)a
1 1 >99 ( 95% yield)b
2 1 >99
3 1 >99
4 1 >99
5 1 >99
6 1 98
[a] Determined by analysis of 1H-NMR of unpurified mixtures.
[L] pure isolated 2a
Example 4 - Example of ether cleavage
o NH4002H (3 equiv.)
SI 0 Pd(0)-AmP-MCF (5 mol%) OH OH
0
Me0 H2 gas , toluene, 80 C, 6h. 40 0 +
Me0o Me0HO 110I +
100% corm
33% 1H-
NMR-comparation 33%
33%
19
CA 02965879 2017-04-26
WO 2016/066835
PCT/EP2015/075333
Example 5 - Example of deoxygenation of aldehydes
A microwave-vial containing a solution of aldehyde (0.1 mmol, 1.0 equiv.),
ammonium formiate (18.9 mg, 0.3
mmol, 3.0 equiv.) and Pd(0)-Nanocatalyst (Pd(0)-AmP-MCF, 6.7 mg, 0.005 mmol, 8
wt%, 5 mol%) in tolu-
ene (0.5 mL) under H2 conditions was stirred at 80 C for 6h.
0 NH4002H (3 equiv.) *
H Pd(0)-AmP-MCF (5 mol%)
OH
________________________________________ )1.
HO HO HO
H2 gas , toluene, 80 C, 6h.
OCH3 OCH3 OCH3
>98% conversion
91 =
9
*Note: - without NH4002H, only alcohol was obtained.
- with 2 equiv of NH4002H, tolyl:alcohol (76:24).
- without Pd(0)-AmP-MCF, <1 % conversion.
Example 6 - General procedure for selective oxidation/depolymerization
sequence
OH OH
TEMPO Cl 0 0
0 = Na0C1
CH2CL2/H20 H
H
H3CO
NaOH, KBr H3C0 H3C0
OCH3 H3C0 02, 3h., pH= 9 OCH3 OCH3
80 =
10 A solution of KBr (1.2 mg, 0.01 mmol, 10 mol /0) in water (1mL)
were added to a solution containing lignin
model (0.1 mmol, 1.0 equiv.) and TEMPO (1.6 mg, 0.01 mmol, 10 mol %) in
CH2Cl2(4mL) and stirred at 0
C. Then, Na0C1 (5.3 g, 10 mmol, 100 equiv.) solution with pH 9 was added drop
wise to the reaction mix-
ture. Afterwards, was added NaOH (2M, 3mL) to the reaction mixture and
connected balloon with 02 and
stirred at 0 C for 3h. After this time, the aqueous layer was extracted two
times with CH2Cl2 and the com-
15 bined organic layers were washed with H20 two times, dried over
anhydrous Na2SO4 and concentrated un-
der reduced pressure. The crude material was purified by silica gel flash
column chromatography obtaining
the major product (Cl product): 1H NMR (500 MHz, CDCI3): d 10.32 (s, 1H), 7.41
(s, 1H), 6.90 (s, 1H), 3.97
(s, 3H), 3.92 (s, 3H). 13C NMR (125.8 MHz, CDCI3): d 188.7, 154.5, 148.4,
132.0, 125.4, 112.4, 109.77, 56.5,
56.2.
20
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Example 7 - Procedure for selective oxidation/depolymerization/demgenation
sequence
A solution of KBr (1.2 mg, 0.01 mmol, 10 mol /0) in water (1mL) were added to
a solution containing "diol
lignin model" (0.1 mmol, 1.0 equiv.) and TEMPO (1.6 mg, 0.01 mmol, 10 mol /0)
in CH2Cl2(4mL) and stirred
at 0 C. Then, Na0C1 (5.3 g, 10 mmol, 100 equiv.) solution with pH 9 was added
drop wise to the reaction
mixture. Afterwards, was added NaOH (2M, 3mL) to the reaction mixture and
connected balloon with 02 and
stirred at 0 C for 3h. After this time, the aqueous layer was extracted two
times with CH2Cl2. The solvent
was removed. Ammonium formiate (18.9 mg, 0.3 mmol, 3.0 equiv.) and Pd(0)-
Nanocatalyst (Pd(0)-AmP-
MCF, 6.7 mg, 0.005 mmol, 8 wt%, 5 mol%) and toluene (0.5 mL) were added. The
reaction was stirred at 80
C for 6h under H2 atmosphere.
OH OH TEMPO (10 mor/o)
CI 0 0
Na0C1 (100 equiv.)
40 0 CH2C12/H20 (4/1)
= H3C0 10
H
NaOH (2M), H3C0 H3C0
OCH3 H
H3C0 KBr (10 mol%) OCH3 OCH3
02, 3h., pH= 9
80 = 20
NH4CO2H (3 equiv.) H2 gas , toluene
80 C, 6h.
Pd(0)-AmP-MCF (5 mol%)
H300
00H3
21
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Example 8 - General procedure for the TEMPO oxidation to ketone
A microwave vial was loaded with diol 3(33.4 mg, 0.1 mmol, 1.0 equiv.) and
TEMPO (0.8 mg, 0.005 mmol, 5
mol%) and flushed with oxygen using 02-balloon for 5 minutes, followed by
addition of 100 pL of a solution
from a mixture of 10 pL of HNO3 in 1 mL acetonitrile and then 100 pL of a
solution from a mixture of 10 pL
HCI in 1 mL acetonitrile. Afterwards acetonitrile (300 pL) and water (30 pL)
was added and then the vial was
sealed and heated to 45 C for 20h. Subsequently, the organic phase was
separated and water phase was
washed with CH2Cl2. The collected organic phases were dried over Na2504, and
concentrated by reduced
pressure. The crude material was further purified by silica chromatography
giving pure products 8 in 99%
yield.
HO HO
HO TEMPO (5 mo154))
HNO3 (10 morfo) 0
00 11)
HCI (10 mol%)
40 OMe
OMe
MeCN:H20 (19:1)
02, 45 C
1110
R3 R3
R2 R2
22
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Example 9 ¨ Screening TEMPO oxidation of dimethoxy benzyl alcohol
To a solution of alcohol 1 (16.8 mg, 0.1 mmol, 1.0 equiv.) in 4 mL of CH2Cl2
and TEMPO (1.6 mg, 0.01
mmol, 10 mol%), an aqueous solution of KBr (1.2 mg, 0.01 mmol, 10 mol%, in 1
mL water) was added at 0
C and the reaction mixture was stirred at 0 C. The fresh aqueous solution of
NaCIO (14% aq.) (2.7 g, 5
mmol, 50 equiv. or 0.53 g, 1 mmol, 10 equiv.) by adjusting pH at 9 with
saturated NaHCO3 . Afterwards 2 M
NaOH (3 mL) was added slowly. The reaction mixture was stirred for lh or 24h
in presence of 02 gas at 0
C. Afterwards the organic phase was separated and water phase was washed with
CH2Cl2. The collected
organic phases were dried over Na2SO4, and concentrated by reduced pressure.
The crude material was
further purified by silica chromatography giving pure products 5.
TEriiiTO
0 CI 0 0
io
Li
11'
... ,
.........r H .I. II,
= ,- H CI .
I
io H
Me I,.L.::::.HMe0 - ' ' MC = -,- = Me0
OMe 1;,-1.2=_H
OMe OMe OMe
I 5a 5b 5c
______________ --- ¨ ¨
entry tile0C: tC:CiUIV time .ii elc F.:iite
:.5a:5b:5cr
1 dis 10 24 n.d 8r,:,I 13
(52: 37 lit'
20 50 1 83 48:62:0
3d,o, 50 1 87 19:(5:6
4 10 24 n.d 86:1.10
5. 50 1 85
(3:j ii3i.i.:(1)1
fad Ai-2 r2C1:1:1 i I 11 H MYR We ceriveH,ii:.- iiir at rci]i_.1. o'..
viici-e"coiXi. ib]
iir bil ciii C-1.-0!1'-'n.:11aphy. IC] Deft.' m IL:Li by '1-i ITiiIR er.,i
ysi..; o'i ort..iic reaci.i.o-i mix!.ure -iiitt Mia
1 chc=r, VV,1:`, r ji ',%'. :KV 0, billeer. ol -lc reaction miti:Hro wiii:.
mii:_ttrillzierii to pH 7 Lic'cio
i.vot k.uo. [fi Ti'ii ri]i oe= of 1-iiii proclitui ciialged aftii.- iivoi,i
23
CA 02965879 2017-04-26
WO 2016/066835
PCT/EP2015/075333
Example 10 - Screening TEMPO oxidation of lignin model
To a solution of diol 3 (33.4 mg, 0.1 mmol, 1.0 equiv.) in 4 mL of CH2Cl2 and
TEMPO (1.6 mg, 0.01 mmol,
mol%), an aqueous solution of KBr (1.2 mg, 0.01 mmol, 10 mol /0, in 1 mL
water) was added at 0 C and
the reaction mixture was stirred at 0 C. The fresh aqueous solution of NaCIO
(14% aq.) (2.7 g, 5 mmol, 50
5 equiv. or 0.53 g, 1 mmol, 10 equiv.) by adjusting pH at 9 with saturated
NaHCO3 . Afterwards 2 M NaOH (3
mL) was added slowly. The reaction mixture was stirred for lh or 24h in
presence of 02 gas at 0 C. After-
wards the organic phase was separated and water phase was washed with CH2Cl2.
The collected organic
phases were dried over Na2SO4, and concentrated by reduced pressure. The crude
material was further
purified by silica chromatography giving pure products 5 and 8.
Ho 01
HO ?CI
OMe L 1 x -":õ..õ1 Ta1150 l,
!', Li-120 0
H H
io CI 0
!' )L 1-10.-A-...0
OMe
'....
N,i0h1 0
OMe CI-1-,C12 OMe OMe OMe
3 Ss 5b 8
Na0Ci :, ') tin=: H-_A _ i,5a:5b:W"
-
Id, e 10 24 n.d 100 c
2d,f 50 1 52 21:70:9
3d 50 1 50 37.3827
4 5'3 1 51
__________________________________________________________________ _
Li ...f_:c)r=jiric, ::) 'H N11%.1HZ the conw, i,_' d I IL_
'_,1_ '311.` %, . r hrjrr: Ij1 ' iehrj 01 :2Jri'icc.i prulL _. 5
arid 8 al:cr s ica :Jr r= l'_:[,!,. I.c] DcluIrri ,_ _:'HI NNW: J-....:Iyk
o' c=i..._-:_ rr action .rixtura
le , Li. F_:_Dr) .., -.L ,1 H .:,/dio.il 0_ IL!' i .:
C_:OFIdUF bi0F1 Or il 0C:tify d,.i-_. :1:1 'rn . Ji
reac.i. ,_:r 'iC vi [L.fijLU k: i_d- :7 : 12 O'C' ' 0 :
.1_4)
24
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Example 11 - Screening TEMPO oxidation of two substituted lignin models
To a solution of alcohol 1 or diol 3 (0.1 mmol, 1.0 equiv.) in 4 mL of CH2Cl2
and TEMPO (1.6 mg, 0.01 mmol,
mol%), an aqueous solution of KBr (1.2 mg, 0.01 mmol, 10 mol%, in 1 mL water)
was added at 0 C and
the reaction mixture was stirred at 0 C. The fresh aqueous solution of NaCIO
(14% aq.) (2.7 g, 5 mmol, 50
5 equiv.) by adjusting pH at 9 with saturated NaHCO3 . Afterwards 2 M NaOH
(3 mL) was added slowly. The
reaction mixture was stirred for lh in presence of 02 gas at 0 C. Afterwards
the organic phase was separat-
ed and water phase was washed with CH2Cl2. The collected organic phases were
dried over Na2SO4, and
concentrated by reduced pressure. The crude material was further purified by
silica chromatography giving
pure products 4.
0
Ho c TF-11 ,=,1 ,..25,..,
I ) L
cy
. . 1 ijLa H . , ,-,
H I 1...yr....i.
Me
I ...I It. i
II L.
I t m2 R2 R2 R2
Ri
1.r3 4.. 4b 4c 4d
,
I
1 la ) 50 1 85 54:30:15
HBO .
)11
21b 50 1 70 .
Bn0
I
HL
3 3s C)Me 50 1 51 29: 51: 0: 20
I
As
k.i-le
F-
HC
4 3t, -Ale 50 1 50 .10:40: 0: 0
All
Dal A, =-or ¨ . 'H : dud 4
Example 12- TEMPO oxidation of three substituted lignin models
To a solution of alcohol 1 or diol 3 (0.1 mmol, 1.0 equiv.) in 4 mL of CH2Cl2
and TEMPO (1.6 mg, 0.01 mmol,
10 mol%), an aqueous solution of KBr (1.2 mg, 0.01 mmol, 10 mol%, in 1 mL
water) was added at 0 C and
the reaction mixture was stirred at 0 C. The fresh aqueous solution of NaCIO
(14% aq.) (2.7 g, 5 mmol, 50
equiv.) by adjusting pH at 9 with saturated NaHCO3 . Afterwards 2 M NaOH (3
mL) was added slowly. The
reaction mixture was stirred for lh in presence of 02 gas at 0 C. Afterwards
the organic phase was separat-
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
ed and water phase was washed with CH2Cl2. The collected organic phases were
dried over Na2SO4, and
concentrated by reduced pressure. The crude material was further purified by
silica chromatography giving
pure products 7.
r.1-1 9 o
R1 [LH
11
R2
R.. 4
Ta 7a 70
ar xamstrata N1I= ay.) time *Bib
Ratio f 7a: 7b70
-14
1 3a 60 1 74 B:80:12
1.11
2 6b 66 1 75
y10 r
53 0:80:20
3 6a ri..) OM 50
'
OM.
+6138
Jo
Gb OW 50 1 52 D:1000
MO
,110
=
Example 13 - Procedure for selective oxidation/depolymerization/deoxygenation
sequence of lign ins
(containing benzylic, allylic or aliphatic alcohols including f3-0-4 aryl
ether linkages):
A solution of KBr (1.2 mg, 0.01 mmol, 10 mol /0) in water (1mL) were added to
a solution containing lignin
(0.1 mmol, 1.0 equiv.) and TEMPO (1.6 mg, 0.01 mmol, 10 mol /0) in CH2Cl2
(4mL) and stirred at 0 C.
Then, Na0C1 (5.3 g, 10 mmol, 100 equiv.) solution with pH 9 was added drop a
drop to the reaction mixture.
Afterwards, was added NaOH (2M, 3mL) to the reaction mixture and connected
balloon with 02 and stirred at
0 C for 3h. After this time, the aqueous layer was extracted two times with
CH2Cl2. The solvent was re-
moved. Ammonium formate (18.9 mg, 0.3 mmol, 3.0 equiv.) and Pd(0)-Nanocatalyst
(Pd(0)-AmP-MCF, 6.7
mg, 0.005 mmol, 8 wt%, 5 mol /0) and toluene (0.5 mL) were added. The reaction
was stirred at 80 C for 6h
under H2 atmosphere.
26
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
Lignin (containing benzylic, allylic or aliphatic alcohols including 0-0-4
aryl ether linkages) was employed as
substrates. The lignin can be milled wood lignin (MWL), cellulolytic enzyme
lignin (CEL), organosolv lignin or
a technical lignin from the pulping processes.
The selective oxidation/depolymerization/deoxygenation sequence of lignins can
be employed using different
transition metal (e.g. Pd, Ir, Ru, Ni, Co, Cu) complexes.
REFERENCES
References for BACKGROUN OF INVENTION
[1] V.S. Ranade, R. Prins, Chem. Eur. J. 2000, 6, 313.
[2] M. Yasuda, Y. Onishi, M. Ueba, T. Miyai, A. Baba, J. Org. Chem. 2001, 66,
7741.
[3] J. Muzart, Tetrahedron 2005, 61, 9423.
[4] C. Haiyan, L. Yongcheng, C. Guangying, H. Guping, W. Li, V. L. Chemistry
of Natural Compounds 2006,
42,407.
[5] N. Thakar, N.F. Polder, K. Djanashvili, H. van Bekkum, F. Kapteijn, J.A.
Moulijn, J.
Catal. 2007, 246, 344.
[6] M. Schlaf, J. Chem. Soc., Dalton Trans. 2006, 4645.
[7] J. Feng, J.-B. Wang, Y.-F. Zhou, H.-Y. Fu, H. Chen, X.-J. Li, Chem. Lett.
2007, 36,1274.
[8] J. Feng, M.-L. Yuan, H. Chen, X.-J. Li, Prog. Chem. 2007, 19, 651.
References for the EXAMPLE section of the DETAILED DESCRIPTION
1. a) E. W. Ping, R. Wallace, J. Pierson, T. F. Fuller and C. W. Jones,
Micropor. Mesopor. Mater., 2010, 132,
174-180
b) M. Shaken, C. Tai, E. &thelid, S. Oscarsson and J. Backvall, Chem. Eur. J.,
2011, 17, 13269-13273
c) E. V. Johnston, 0. Verho, M. D. Karkas, M. Shaken, C. Tai, P. Palmgren, K.
Eriksson, S. Oscarsson and
J. Backvall, Chem. Eur. J., 2012, 18, 12202-12206
d) L. Deiana, S. Afewerki, C. Palo-Nieto, 0. Verho, E. V. Johnston and A.
Cordova, Sci. Rep., 2012, 2, 851.;
D01:10.1038/srep00851
2. a) E. W. Ping, R. Wallace, J. Pierson, T. F. Fuller and C. W. Jones,
Micropor. Mesopor. Mater., 2010, 132,
174-180
b) M. Shaken, C. Tai, E. Gothelid, S. Oscarsson and J. Backvall, Chem. Eur.
J., 2011, 17, 13269-13273
c) E. V. Johnston, 0. Verho, M. D. Karkas, M. Shaken, C. Tai, P. Palmgren, K.
Eriksson, S. Oscarsson and
J. Backvall, Chem. Eur. J., 2012, 18, 12202-12206
27
CA 02965879 2017-04-26
WO 2016/066835 PCT/EP2015/075333
d) L. Deiana, S. Afewerki, C. Palo-Nieto, 0. Verho, E. V. Johnston and A.
Cordova, Sci. Rep., 2012, 2, 851.;
D01:10.1038/srep00851
3. Buser et al., Chemical Communications, 2014, 50(32), 4234.
4. Berger et al., Magnetic Resonance in Chemistry, 2013, 51(12), 815.
5. Lancaster et al., Photochemistry and Photobiology, 2014, 90(2), 394.
6. Nyquist et al., Applied Spectroscopy, 1991, 45, 1649
7. Eisch et al., Organometallics, 2005, 24, 3355.
8. a) E. W. Ping, R. Wallace, J. Pierson, T. F. Fuller and C. W. Jones,
Micropor. Mesopor. Mater., 2010, 132,
174-180
lo b) M. Shaken, C. Tai, E. Gothelid, S. Oscarsson and J. Backvall, Chem.
Eur. J., 2011, 17, 13269-13273
c) E. V. Johnston, 0. Verho, M. D. Karkas, M. Shaken, C. Tai, P. Palmgren, K.
Eriksson, S. Oscarsson and
J. Backvall, Chem. Eur. J., 2012, 18, 12202-12206
d) L. Deiana, S. Afewerki, C. Palo-Nieto, 0. Verho, E. V. Johnston and A.
Cordova, Sci. Rep., 2012, 2, 851.;
D01:10.1038/srep00851
28